When Leo invites his hip and trendy ex-girlfriend to a friendly dinner party, Grace turns to Will, Jack and Karen to round out the guest list and keep the night running smoothly. However, when Leo's ex turns out to be the only girl Will ever slept with, Grace's jealousy gets the better of her. Meanwhile, Karen discovers Lorraine's dog Chompers hiding in Stan's closet and searches for a new owner for the puppy.

In a flashback to Thanksgiving 1985, coed Grace invites her college boyfriend Will home to meet her family, but their romantic relationship swerves dramatically when a conflicted Will phones a teenaged Jack for some crucial advice. Unfortunately, Will and an angry Grace end up temporarily estranged when he blurts out the truth and she orders him out of the house -- and her life.

Matt Damon makes a guest appearance as a clever charmer named Owen, who's competing against Jack for a spot in New York's Gay Men's Chorus. Truth be told, however, Owen is totally straight and is really after the group's big perk: a summer trip to Europe, all-expenses paid. Jack suspects Owen's ruse but needs proof. How about the hug test? Now a flustered Jack reluctantly turns to Grace to ""in"" Owen. Meanwhile, a scheming Karen tries to pass off an unwitting Will as her lover and not her lawyer when she discovers that she's the object of pity for being single at her own Valentine's Day party

Will and Grace are shocked to learn that Jack never told his mother he was gay and encourage him to open up to her at Thanksgiving. The evening brings a revelation for Jack as well: his father isn't who he thinks it is.

In a flashback to Thanksgiving 1985, coed Grace invites her college boyfriend Will home to meet her family, but their romantic relationship swerves dramatically when a conflicted Will phones a teenaged Jack for some crucial advice. Unfortunately, Will and an angry Grace end up temporarily estranged when he blurts out the truth and she orders him out of the house -- and her life.

While a baleful Grace wallows in bed as she grieves over losing her boyfriend Nathan, an enterprising Will tries all his old tricks to spring her from her mattress and back into the real world's whirl. But when Jack and Karen arrive, Will fears that their bizarre efforts to help might actually drive Grace futher into her shell -- not to mention therapy.

Will reluctantly decides to use a birthday gift certificate from Grace to consult a psychic about his future and encounters an absent-minded fortune teller whose frighteningly personal predictions leave him reeling. Elsewhere, a guilt-ridden Grace hires a lackadaisical waiter whom she helped to get fired while Jack, who forever idolizes music, TV and film legend Cher, stumbles onto the real deal and meets the Oscar winner herself -- whom he mistakes for a drag queen.

The culmination of eight seasons ends tonight with a one-hour series finale - will Will and Grace raise a child together and find ultimate happiness? Will Jack find anyone that loves him as much as he loves himself? Will Karen find true happiness with the absence of Stan? All these questions and more will be answered as this groundbreaking series concludes eight amazing seasons.

A deceiving, but flattering, newspaper photo makes Grace look more "endowed" than she really is and gains her the attention of a former high school heartthrob who was never one to keep abreast of her before. Jack is destroyed to learn that Will had a fling with Walter, Jack's ex-boyfriend.

While on a blind date, Will finds out that Karen's husband Stan has had a heart attack and rushes to the hospital to be with the gang. Will, Jack, Grace, and Rosario all speculate on who Karen will turn to for her inevitable emotional breakdown. After all, who will pay the bills if Stan dies?

Rather than be apart on Thanksgiving Day, Will and Grace join Jack and Karen for a festive holiday motor tour of their respective dysfunctional families, including Grace's domineering mother as well as Will's willful mom and Jack's stepdad -- with unsettling results. Meanwhile, back home, a waiting Rosario bastes and tastes their juicy turkey.

This episode is also known as "Thanksgiving." Will and Grace join Jack and Karen in a motor tour of their respective families. (Double-length Episode)

Grace contemplates having an affair with a married man. Elsewhere, Jack begins new career as a host of his new talk show "Jack Talk." Will gets some advice from Malcolm and tries to hide from Karen the fact that Stan is alive.

An unemployed Will agrees to serve as one of Jack's cater-waiters, until he learns that he'll be catering for American Bar Association. Grace discovers Karen's darkest secret: she once made a porn video.

The "Sound of Music Sing-Along" has come to town and no one is more excited than Grace. She plans for her and Will to attend the musical in character-like style by dressing up in costumes.

Grace's visiting mom, Bobbi Adler, a would-be star whose propensity for breaking out into show tunes and impressions dismays her daughter – and delights Will, Jack and Karen – wreaks havoc by suggesting Will and Grace wed, despite their sexual differences. When Will winces at the fantasy of committing to anyone who needs to be the star of a relationship, Grace realizes she's more of a chip off the old block than she imagined.

An exasperated Grace tries to mediate between a resentful Will and her sloppy, free-spirited boyfriend Nathan when Nathan moves in while Jack is in a royal dither as he plans to finally meet his unseen father face-to-face. However, Grace grows nervous when the two polar-opposite men find some common ground and she ponders how a devoted boyfriend might affect her equally important relationship with her longtime buddy Will. After settling his father issues, Jack later gets the surprise of his life in a most unexpected fashion.

An exasperated Grace tries to mediate between a resentful Will and her sloppy, free-spirited boyfriend Nathan when Nathan moves in while Jack is in a royal dither as he plans to finally meet his unseen father face-to-face. However, Grace grows nervous when the two polar-opposite men find some common ground and she ponders how a devoted boyfriend might affect her equally important relationship with her longtime buddy Will. After settling his father issues, Jack later gets the surprise of his life in a most unexpected fashion.

Jack is puffed up with paternal pride as he escorts his long-lost teenaged son Elliot to a junior high school dance but not before he coerces Grace into posing as Elliot's date – which only revives her own tortured memories of rejection from school dances many years before. Elsewhere, Karen has great fun at her lawyer Will's expense when she continues to capriciously summon him for bogus ""emergencies"" – that is, until she really needs him.

Opting out of the annual Grace Adler Design Christmas party, ultimate ""Fanilow"" Will spends the night waiting in line for tickets to a special Barry Manilow concert only to have his weak bladder force him to make a quick pit stop and entrust Grace to hold his place. However, Will's snubbing of an overweight man in the bathroom line leaves his chances of meeting his idol in doubt. Meanwhile, a distraught Grace discovers her mother has cancelled on their annual Hanukkah shopping spree to have dinner with Jack. And Karen is embraced by the inspiring music of Manilow waiting in line with a Fanilow named Cheryl.

When Vince's mother injures her leg and is unable to make her traditional Italian Thanksgiving, Will comes to the rescue by offering to make his own special dinner, but Vince's mother refuses to give Will any credit. Meanwhile, Jack gives Vince's sister Ro a few pointers on a big secret she is keeping from her family and fiancé. Meanwhile, Grace and Karen get very cozy with Vince's much younger cousin.

When Vince's mother injures her leg and is unable to make her traditional Italian Thanksgiving, Will comes to the rescue by offering to make his own special dinner, but Vince's mother refuses to give Will any credit. Meanwhile, Jack gives Vince's sister Ro a few pointers on a big secret she is keeping from her family and fiancé. Meanwhile, Grace and Karen get very cozy with Vince's much younger cousin.

Karen celebrates her birthday with some of New York's crème de la crème, but the festivities turn sour when she ends up crammed in the bathroom with Grace, Will and Jack, who have all embarrassed themselves at the party.

Grace is jealous when her mother stops match making for her, and instead sets Will up. Jack must convince an INS agent (who he dated once) that he and Rosario are happily married.

Despite their history, Grace spends a fun evening with Val [ from ep. # 18 Grace, Replaced] only to have Will suspect her of stealing. Meanwhile Jack becomes attracted to the leader of Welcome Home-an organization for gays who have converted to going straight, so he acts straight to woo the man.